• Title/Summary/Keyword: safe distance

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Simplified Module Based Self-collision Detection for Humanoid Robots (간략화 된 모듈 기반의 휴머노이드 로봇을 위한 자기충돌 탐지)

  • Kwak, Hwan-Joo;Park, Gwi-Tae
    • Proceedings of the KIEE Conference
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    • 2008.04a
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    • pp.240-241
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    • 2008
  • We are presenting the efficient and robust simplified module based self-collision detection of humanoid robot simulator. For safe and reliable operations of humanoid robot, the self-collision detection is essential and extremely important. The main methods of self-collision detection are inverse X-Y-Z fixed angles and module distance filtering (MDF). According to experiments on the humanoid robot simulator with the self-collision detection, we could have a confidence about the efficiency of the self-collision.

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Dehydration by Electro-osmosis on Ceramic Body (Electro-osmosis에 의한 Dehydration)

  • Han, Sang-Mok
    • Journal of Industrial Technology
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    • v.4
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    • pp.43-46
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    • 1984
  • In process of water removing safely from plastic clay, an electric field applied to a wet, porous solid such as day usually causes the rapid dehydration. The water-bearing positive ions move to negative electrode under the d. c. electrical stress or field. Therefore application of electro-osmosis to wet clay could include drying thick and large-scale ceramic body quickly and evenly. The d. c. power supply unit to 60 volts is necessary for safe practice. Also wider contact area and shorter distance between electrodes accelerate effectively the removal of water.

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Obstacle Avoidance of Mobile Robot using Scan Code Method (스캔코드법을 이용한 이동로봇의 장애물 회피)

  • Cho, Gyu-Sang
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2856-2858
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    • 2000
  • This paper proposes a scan code method for obstacle avoidance of mobile robot. Obstacles detected in a circular window are converted to scan codes and then to the steering angle. The safe rotating radius is obtained by the scan code to avoid the collision between robot and obstacle and. the minimum distance for rotation is calculated. Effectiveness of the method is illustrated through simulations, and the results show that the proposed method can be efficiently implemented to an unknown environment.

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Hazard Distance from Hydrogen Accidents (수소가스사고의 피해범위)

  • Jo, Young-Do
    • Journal of the Korean Institute of Gas
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    • v.16 no.1
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    • pp.15-21
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    • 2012
  • An analysis was completed of the hazards distance of hydrogen accidents such as jet release, jet fire, and vapor cloud explosion(VCE) of hydrogen gas, and simplified equations have been proposed to predict the hazard distances to set up safety distance by the gas dispersion, fire, and explosion following hydrogen gas release. For a small release rate of hydrogen gas, such as from a pine-hole, the hazard distance from jet dispersion is longer than that from jet fire. The hazard distance is directly proportional to the pressure raised to a half power and to the diameter of hole and up to several tens meters. For a large release rate, such as from full bore rupture of a pipeline or a large hole of storage vessel, the hazard distance from a large jet fire is longer than that from unconfined vapor cloud explosion. The hazard distance from the fire may be up to several hundred meters. Hydrogen filling station in urban area is difficult to compliance with the safety distance criterion, if the accident scenario of large hydrogen gas release is basis for setting up the safety distance, which is minimum separation distance between the station and building. Therefore, the accident of large hydrogen gas release must be prevented by using safety devices and the safety distance may be set based on the small release rate of hydrogen gas. But if there are any possibility of large release, populated building, such as school, hospital etc, should be separated several hundred meters.

Path Planning and Tracking for Mobile Robots Using An Improved Distance Transform Algorithm (개선된 거리변환 알고리즘을 이용한 이동 로봇의 경로 계획 및 추적)

  • Park Jin-Hyun;Park Gi-Hyung;Choi Young-Kiu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.4
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    • pp.782-791
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    • 2005
  • In this paper, path planning and tracking problems are mentioned to guarantee efficient and safe navigation of autonomous mobile robots. We focus on the path planning and also deal with the path tracking and obstacle avoidance. We improved the conventional distance transform (DT) algorithm for the path planning. Using the improved DT algorithm, we obtain paths with shorter distances compared to the conventional DT algorithm. In the stage of the Path tracking, we employ the fuzzy logic controller to conduct the path tracking behavior and obstacle avoidance behavior. Through computer simulation studies, we show the effectiveness of the Nosed navigational algorithm for autonomous mobile robots.

Design and Analysis of Collision Alarm Using Infrared Distance Sensor (적외선 거리 센서를 사용한 충돌 경보기 설계 및 특성 분석)

  • Kim, Byoung-Ho
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.6
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    • pp.634-639
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    • 2014
  • This paper specifies a collision alarm using an infrared distance sensor that can identify the dangerousness of collision of active mobile robotic systems to various objects, such as unknown objects or another robots. And we analyse the major operating signals and features of the collision alarm for effective industrial applications. For the purpose, we consider a typical parking situation of a mobile robotic system with the collision alarm designed. As a result, it is shown that the proposed collision alarm is applicable for effective collision avoidance and safe driving of various mobile robots or vehicles.

Path Planning and Tracking for Mobile Robots Using An Improved Distance Transform Algorithm (개선된 거리변환 알고리즘을 이용한 이동 로봇의 경로 계획 및 추적)

  • Park, Jin-Hyun;Park, Gi-Hyung;Choi, Young-Kiu
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.295-299
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    • 2005
  • In this paper, path planning and tracking problems are mentioned to guarantee efficient and safe navigation of autonomous mobile robots. We focus on the path planning and also deal with the path tracking and obstacle avoidance. We improved the conventional distance transform (DT) algorithm for the path planning. Using the improved DT algorithm, we obtain paths with shorter distances compared to the conventional DT algorithm. In the stage of the path tracking, we employ the fuzzy logic controller to conduct the path tracking behavior and obstacle avoidance behavior. Through computer simulation studies, we show the effectiveness of the proposed navigational algorithm for autonomous mobile robots.

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Safety Evaluation of the Lighting at the Entrance of a Very Long Road Tunnel: A Case Study in Ilam

  • Mehri, Ahmad;Hajizadeh, Roohalah;Dehghan, Somayeh Farhang;Nassiri, Parvin;Jafari, Sayed Mohammad;Taheri, Fereshteh;Zakerian, Seyed Abolfazl
    • Safety and Health at Work
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    • v.8 no.2
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    • pp.151-155
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    • 2017
  • Background: At the entrance of a tunnel, reflection of sunlight from the surrounding environment and a lack of adequate lighting usually cause some vision problems. The purpose of this study was to perform a safety evaluation of lighting on a very long road in Ilam, Iran. Methods: The average luminance was measured using a luminance meter (model S3; Hagner, Solna, Sweden). A camera (model 108, 35-mm single-lens reflex; Yashica, Nagano, Japan) was used to take photographs of the safe stopping distance from the tunnel entrance. Equivalent luminance was determined according to the Holliday polar diagram. Results: Considering the average luminance at the tunnel entrance ($116.7cd/m^2$) and using Adrian's equation, the safe level of lighting at the entrance of the tunnel was determined to be 0.7. Conclusion: A comparison between the results of the safe levels of lighting at the entrance of the tunnel and the De Boer scale showed that the phenomenon of black holes is created at the tunnel entrance. This may lead to a misadaptation of the drivers' eyes to the change in luminance level at the entrance of the tunnel, thereby increasing the risk of road accidents in this zone.

Review on the Point Location and Locating Method of GB18 (승령(GB18) 혈위와 취혈 방법에 대한 고찰)

  • Koo, Sungtae
    • Korean Journal of Acupuncture
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    • v.35 no.4
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    • pp.203-209
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    • 2018
  • Objectives : The GB18 belongs to one of the 92 controversial points in the development of WHO standard of acupuncture point location. The number of Chon measurement of GB18 is described differently in the A-B Classic of Acupuncture and Moxibustion (ChimGuGakEulKyung; AB Classic) and the Complete Compendium of Acupuncture and Moxibustion(ChimGuDaeSeong; Complete Compendium). The aim of the study is to review the point location of GB18 and compare the relation of the location of BL7. In addition, I would like to propose new locating method of GB18. Methods : In order to review I examined the expressions of the location of GB18 and the mapping location on the acupuncture chart in the landmark classic acupuncture literatures. Results : In the most literatures, the location of GB18 was described by the distance from the GB17. The distance was 1.5 chon with one exception of 1 chon. The intervals from GB15 to GB18 was 1 chon or 1.5 chon. Although the distance from the anterior hairline is the same as 4 chon, mapping points of GB18 and BL7 on the acupuncture chart were different. Conclusions : Consequently, in the AB Classic, meaning of the location is the actual distance of scalp surface. In the Complete Compendium, however, meaning of the location is the hypothetical distance in the imaginary scalp surface. Therefore, it is safe to find the GB18 on the same level with GV20 on the connecting line of bilateral auricular apexes. The relation of GB18 and BL7 should be reconsidered.

Triathlon-Related Overuse Injury and Medical Issues (트라이애슬론의 과사용 부상과 의학적 위험요인에 대한 고찰)

  • Park, Chan-Ho;Kwak, Yi-Sub;Kim, Tae-Un
    • Journal of Life Science
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    • v.20 no.2
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    • pp.314-320
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    • 2010
  • As the nature of triathlons is competition in three successive sports, triathletes experience elevated levels of stress on the body that are absent in single-sport athletic events, and consequently there are more potential medical problems to prepare for. Triathletes can also experience problems such as hypothermia, heat illness, excessive exposure to ultraviolet radiation, musculoskeletal injuries and trauma, immunosuppression, and haemolysis. Depending on the potentiality of such above-listed problems occurring in any given race, race organizers will prepare preventative measures and treatments accordingly. Olympic distance is not the only triathlon racing distance. Sprints, which are normally around half the Olympic distance, are common distances, as well as Long (2 km swim, 80 km bike, 20 km run), Ironman (3.8 km swim, 180 km bike, 42 km run), and ultra-distance events varying in length. Races of longer duration normally result in a higher percentage of athletes experiencing the above-mentioned medical problems, as well as inducing additional health risks such as hyponatraemia. Minimizing the occurrences of serious health issues is possible through the following means: carefully preparing for the probable race-day weather conditions; proper management and organization of the race; preparing an extensive water-safety and ground-course safety plan; distributing necessary nutrition along the course; and stressing the importance for athletes to have proper knowledge concerning race nutrition, biomechanical technique, physical preparation, and utilization of safe equipment. While risks of competing in triathlon are many, the instances of such medical problems are not excessive, and the triathlon has a reputation of being a reasonably safe sport as long as athletes with high risk take added precautions.